1. Field of the Invention
The present invention relates to a data processing apparatus, a data processing system and a data transmitting method for communicating data to an external storage apparatus by using a serial interface, and to an external storage apparatus adaptable to the data processing apparatus, the data processing system and the data transmitting method.
2. Related Background Art
Hitherto, a data processing apparatus, to which a memory card including a storage medium, such as a flush memory, is connected, has been known. A conventional data processing apparatus of the foregoing type and a memory card arranged to be connected to the data processing apparatus will now be described with reference to the drawings.
As shown in FIG. 1, a data processing apparatus 100 includes a data processing block 101, a register 102, a host side serial interface circuit 103 and a host side controller 104. The memory card 110 includes a memory 111, a register 112, a card side serial interface circuit 113 and a card side controller 114.
The data processing block 101 of the data processing apparatus 100 reads data stored on the memory card 110 to subject read data to a variety of processes. Moreover, the data processing block 101 performs the variety of the data processes to generate data which will be written on the memory card 110. That is, the data processing block 101 serves as a data processing circuit for a variety of apparatuses of a type which uses the memory card 110.
The register 102 is a buffer between the data processing block 101 and the host side serial interface circuit 103. That is, when data is supplied from the data processing block 101 to the host side serial interface circuit 103, the data processing apparatus 100 temporarily stores data on the register 102, and then supplies data to the host side serial interface circuit 103. Similarly, the data processing apparatus 100 temporarily stores data in the register 102, and then supplies data to the data processing block 101 when data is supplied from the host side serial interface circuit 103 to the data processing block 101.
The host side serial interface circuit 103 converts data supplied from the data processing block 101 through the register 102 and a command supplied from the card side controller 114 into serial signals so as to supply the serial signals to the memory card 110. Moreover, the host side serial interface circuit 103 converts data of the serial signal and the command supplied from the memory card 110 into parallel signals so as to supply the parallel signals to the data processing block 101 and the card side controller 114.
The host side serial interface circuit 103 supplies a synchronizing signal (CLK) of data and the command and a chip-selection signal (CS) to the memory card 110. The host side serial interface circuit 103 acquires a busy signal (BUSY) and an interrupt signal (INTERRUPT) supplied from the memory card 110.
The host side controller 104 controls the data processing operation which is performed by the data processing block 101 and a data transmitting operation which is performed by the host side serial interface circuit 103. The host side controller 104 supplies a command, which is a control command for the memory card 110, to the memory card 110 through the register 112.
On the other hand, the memory 111 of the memory card 110 includes, for example, a flush memory, on which data supplied from the data processing block 101 is stored.
The register 112 is a buffer between the memory 111 and the card side serial interface circuit 113. That is, the memory card 110 temporarily stores data on the register 102, and then supplies data, which must be written, to the memory 111 when data supplied from the data processing apparatus 100 is written on the memory 111. Similarly, the memory card 110 temporarily stores data on the register 102, and then supplies data, which must be read, to the card side serial interface circuit 113 when the data processing apparatus 100 reads data from the memory 111. That is, the register 112 is a circuit having a function to serve as a page buffer for the flush memory.
The card side serial interface circuit 113 is controlled by the card side controller 114 in such a manner as to convert data of the parallel signal supplied from the memory 111 and the command supplied from the card side controller 114 into serial signals so as to supply the serial signals to the data processing apparatus 100. The card side serial interface circuit 113 converts data of the serial signal and the command supplied from the data processing apparatus 100 into parallel signals so as to supply the parallel signals to the memory 111 and the card side controller 114.
The card side serial interface circuit 113 acquires the synchronizing signal (CLK) of data and the command and the chip-selection signal (CS) from the data processing apparatus 100. The card side serial interface circuit 113 supplies the busy signal (BUSY) and the interrupt signal (INTERRUPT) to the data processing apparatus 100.
The card side controller 114 controls data storage, reading and erasing operations which are performed by the memory 111 in accordance with a command or the like supplied from the data processing apparatus 100. The card side controller 114 controls the data transmitting operation which is performed by the card side serial interface circuit 113. The host side controller 104 acquires, from the memory card 110, the busy signal and the interrupt signal which serve as status signals for the memory card 110.
An operation for transmitting data between the data processing apparatus 100 and the memory card 110 is performed through a transmission line arranged between the host side serial interface circuit 103 and the card side serial interface circuit 113.
Between the card side serial interface circuit 113 of the data processing apparatus 100 and the card side serial interface circuit 113 of the memory card 110, there are arranged five signal lines consisting of a CLK line, a CS line, a DT line, a BUSY line and an INT line.
The DT line is supplied with main data, that is, data processed by the data processing block 101 so as to be written on the memory 111 and data which must be written from the memory 111 so as to be supplied to the data processing block 101. Moreover, a command which is supplied from the data processing apparatus 100 to the memory card 110 and which serves as a control command and a command which is supplied from the memory card 110 to the data processing apparatus 100 are transmitted to the DT line. That is, main data and the command formed into serial signals are bidirectionally transmitted to the DT line.
A synchronizing signal of main data and the commands which are transmitted to the DT line is supplied from the data processing apparatus 100 to the memory card 110 through the CLK line.
The so-called chip select signal is supplied from the data processing apparatus 100 to the memory card 110 through the CS line. In a period of time in which the level of the chip select signal is high, a fact is indicated that main data, the commands and the synchronizing signals are effective.
The busy signal indicating that the memory card 110 is performing a process is transmitted to the BUSY line. When the memory card 110 is performing, for example, a writing process and an access which is made from the data processing apparatus 100 is inhibited, the busy signal is supplied from the memory card 110 to the data processing apparatus 100.
The interrupt signal indicating an interruption from the memory card 110 to the data processing apparatus 100 is supplied from the memory card 110 to the data processing apparatus 100 through the INT line.
The variety of the signals are transmitted through the above-mentioned transmitting lines in accordance with a time chart arranged as shown in FIG. 2. With reference to the time chart shown in FIG. 2, a process for reading data stored in the memory card 110 will now be described.
At time t11, the data processing apparatus 100 supplies the chip select signal to the memory card 110 through the CS line. In addition to the chip select signal, the data processing apparatus 100 supplies the synchronizing signal through the CLK line. When the memory card 110 has acquired the chip select signal, the memory card 110 prepares for acquiring a command which will be supplied from the data processing apparatus 100. When the data processing apparatus 100 has supplied the chip select signal, the data processing apparatus 100 supplies a reading command and its address to the memory card 110 through the DT line.
After the data processing apparatus 100 has supplied the reading command and the like, the data processing apparatus 100 interrupts the operation for supplying the command and the synchronizing signal at time t12. After the memory card 110 has acquired the command, the memory card 110 supplies the busy signal to the data processing apparatus 100 in order to perform the control in accordance with the supplied command. That is, the memory card 110 performs control to read main data at an instructed address from the memory 111 so as to supply main data to the register 112. At this time, the data processing apparatus 100 does not interrupt supply of the chip select signal.
When the memory card 110 has read and supplied main data to the register 112, the memory card 110 interrupts supply of the busy signal at time t13. That is, the memory card 110 communicates, to the data processing apparatus 100, a ready state in which a preparation for transmitting main data has been completed.
After the data processing apparatus 100 has detected interruption of supply of the busy signal, the data processing apparatus 100 makes a determination that the control which is performed in accordance with the command supplied from the memory card 110 has been completed. Thus, the data processing apparatus 100 supplies a synchronizing signal to the memory card 110 at time t14. Then, the memory card 110 transmits main data to the data processing apparatus 100 through the DT line.
After the memory card 110 has completed transmission of main data, the data processing apparatus 100 interrupts supply of the synchronizing signal and the chip select signal at time t15.
If the reading process and the like have changed the internal state of the memory card 110, at time t16, the memory card 110 supplies the interrupt signal indicating interruption to the data processing apparatus 100 through the INT line. When the interrupt signal has been supplied to the data processing apparatus 100, the data processing apparatus 100 supplies a predetermined command and the chip select signal to the memory card 110 in order to acquire a cause of this interruption from the memory card 110.
As described above, the data processing apparatus 100 has the DT line for transmitting main data and the commands, the CLK line for supplying the synchronizing signal, the CS line for supplying the chip select signal, the BUSY line for acquiring the busy signal and the INT line for acquiring the interrupt signal so as to communicate data to and from the memory card 110.
When size reduction of the memory card 110 which is the external storage apparatus is attempted, the number of signal lines arranged between the data processing apparatus 100 and the memory card 110 must be reduced.
In view of the foregoing, an object of the present invention is to provide a data processing apparatus, an external storage apparatus, a data processing system and an external storage apparatus for use in the data transmitting method arranged to transmit data by using serial signals and capable of reducing the number of signal lines for transmitting serial data.
To achieve the above-mentioned object, according to one aspect of the present invention, there is provided a data processing apparatus including: a serial signal I/O block for communicating data to an external storage apparatus by using serial signals; a control signal output block for supplying, to the external storage apparatus, a control signal for controlling transmitting timing of data which is transmitted by the serial signal I/O block; and a synchronizing signal output block for supplying, to the external storage apparatus, a synchronizing signal of data which is transmitted by the serial signal I/O block, wherein the serial signal I/O block transmits data in a period of time in which the control signal output block supplies the control signal to the external storage apparatus and acquires a status signal indicating a state of the operation of the external storage apparatus from the external storage apparatus in a period of time in which the control signal is not supplied from the control signal output block to the external storage apparatus.
The data processing apparatus has the structure that the serial signal I/O block acquires a status signal from the external storage apparatus in a period of time in which the serial signal I/O block does not supply the control signal so as to transmit both of data and the status signal.
According to another aspect of the present invention, there is provided an external storage apparatus including: a serial signal I/O block for communicating data to a data processing apparatus by using serial signals; a control signal input block for acquiring, from the data processing apparatus, a control signal for controlling transmitting timing of data which is transmitted by the serial signal I/O block; and a synchronizing signal input block for acquiring, from the data processing apparatus, a synchronizing signal of data which is transmitted by the serial signal I/O block, wherein the serial signal I/O block transmits data in a period of time in which the control signal input block is supplied with the control signal and transmits a status signal indicating a state of the operation of the external storage apparatus in a period of time in which the control signal input block is not supplied with the control signal.
The external storage apparatus has the structure that the serial signal I/O block supplies a status signal to the data processing apparatus in a period of time in which the control signal is not supplied so as to transmit both of data and the status signal.
According to another aspect of the present invention, there is provided a data processing system including: data processing means incorporating a host side serial signal I/O block for communicating data by using serial signals, a control signal output block for transmitting a control signal for controlling transmitting timing of data which is transmitted by the host side serial signal I/O block and data processing means for supplying a synchronizing signal of data which is transmitted by the host side serial signal I/O block; and external storage means incorporating an external serial signal I/O block for communicating data to the host side serial signal I/O block of the data processing means, a control signal input block for acquiring the control signal and a synchronizing signal input block for acquiring the synchronizing signal, wherein the host side serial signal I/O block and the external serial signal I/O block communicate data in a period of time in which the control signal is supplied and the external serial signal I/O block supplies, to the host side serial signal I/O block, a status signal indicating a state of the operation of the external storage means in a period of time in which the control signal is not supplied to the control signal input block.
The data processing system has the structure that the external serial signal I/O block supplies the serial signal to the data processing means in a period of time in which the external serial signal I/O block is not supplied with the control signal and acquires the status signal from the external storage means in a period of time in which the host side serial signal I/O block does not supply the control signal so as to transmit both of data and the status signal.
According to another aspect of the present invention, there is provided a data transmitting method for communicating data between a data processing apparatus and an external storage apparatus for the data processing apparatus, including the steps of: generating a control signal for controlling data transmission timing; transmitting data in response to the control signal generated by the data processing apparatus; and transmitting a status signal indicating a state of the operation of the external storage apparatus in a period of time in which data transmission which is performed in response to the control signal is not performed.
The data transmitting method has the structure that the status signal indicating a state of the operation of the external storage apparatus is transmitted in a period of time in which data is not transmitted in response to the control signal so as to be transmit both of data and the status signal by one transmitting means.
According to another aspect of the present invention, there is provided a data processing apparatus including: a serial signal I/O block for communicating data to an external storage apparatus by using serial signals; a control signal output block for supplying, to the external storage apparatus, a control signal for controlling timing at which data which is transmitted by the serial signal I/O block is switched and supplying the control signal to the external storage apparatus; and a synchronizing signal output block for supplying, to the external storage apparatus, a synchronizing signal of data which is transmitted by the serial signal I/O block, wherein the serial signal I/O block, in response to the control signal, switches the contents of data which is transmitted.
The data processing apparatus has the structure that the contents of data which is transmitted in response to the control signal are switched so that the serial signal I/O block transmits data of a plurality of contents. According to another aspect of the present invention, there is provided an external storage apparatus including: a serial signal I/O block for communicating data to a data processing apparatus by using serial signals; a control signal input block for acquiring, from the data processing apparatus, a control signal for controlling timing at which data which is transmitted by the serial signal I/O block is switched; and a synchronizing signal input block for acquiring, from the data processing apparatus, a synchronizing signal of data which is transmitted by the serial signal I/O block, wherein the serial signal I/O block, in response to the control signal, switches the contents of data which is transmitted.
The external storage apparatus has the structure that the contents of data which is transmitted in response to the control signal are switched so that the serial signal I/O block transmits data of a plurality of contents. According to another aspect of the present invention, there is provided a data processing system including: data processing means incorporating a host side serial signal I/O block for transmitting data by using serial signals, a control signal output block for generating a control signal for controlling timing at which data which is transmitted by the host side serial signal I/O block is switched and a synchronizing signal output block for transmitting a synchronizing signal of data which is transmitted by the host side serial signal I/O block so that the data processing means processes data; and external storage means incorporating an external serial signal I/O block for communicating data to the host side serial signal I/O block, a control signal input block for acquiring the control signal transmitted from the control signal output block, and a synchronizing signal input block for acquiring the synchronizing signal transmitted from the synchronizing signal output block, the external storage means being connected to the data processing means so as to store data which is processed by the data processing means, wherein the host side serial signal I/O block and the external serial signal I/O block switch the contents of data which is transmitted in response to the control signal.
The data processing system has the structure that the contents of data which is transmitted in response to the control signal are switched so that the host side serial signal I/O block and the external serial signal I/O block transmit data of a plurality of contents.
According to another aspect of the present invention, there is provided a data transmitting method including the steps of: causing the data processing apparatus and the external storage apparatus to communicate data by using serial signals; causing the data processing apparatus to generate a control signal for controlling timing at which data which is transmitted is switched and to transmit the control signal to the external storage apparatus; and causing the data processing apparatus and the external storage apparatus to switch the contents of data which is transmitted in response to the control signal.
The data transmitting method according to the present invention has the structure that the contents of data which is transmitted in response to the control signal are switched so that the data processing apparatus and the external storage apparatus transmit data of a plurality of contents by one transmitting means.
According to another aspect of the present invention, there is provided a data processing apparatus including: a serial signal I/O block for performing data communication to an external storage apparatus; a control signal output block for supplying, to the external storage apparatus, a control signal for controlling timing at which data which is communicated to the serial signal I/O block is switched; and a synchronizing signal output block for supplying, to the external storage apparatus, a synchronizing signal of data which is communicated by the serial signal I/O block. The serial signal I/O block performs, by using serial signals, at least transmitting, to an external storage apparatus, data of a control command for controlling the operation of the external storage apparatus, receiving a status signal indicating a state of the operation of the external storage apparatus from the external storage apparatus, transmitting, to the external storage apparatus, data which is written on the external storage apparatus and receiving data read from the external storage apparatus.
The control signal output block makes the signal level of the control signal which is supplied to the external storage apparatus to be a predetermined level in accordance with data which is communicated by the serial signal I/O block. When the serial signal I/O block is receiving the status signal, the serial signal I/O block makes a determination that the status signal is a ready signal indicating a fact that the external storage apparatus is in a state for waiting input of a signal in a case where the status signal is a signal having the signal level which is repeatedly changed at predetermined cycles. In other cases, the serial signal I/O block makes a determination that the status signal is a busy signal indicating a fact that the external storage apparatus is in a state in which the external storage apparatus does not receive an input of a signal.
The data processing apparatus has the structure that the signal level of the control signal which is supplied to the external storage apparatus in accordance with data which is communicated by the serial signal I/O block is made to be a predetermined level. The data processing apparatus has the structure that a determination is made that the status signal is the ready signal if the received status signal is a signal having the signal level which is repeatedly changed at predetermined cycles. In other case, a determination is made that the status signal is the busy signal.
According to another aspect of the present invention, there is provided an external storage apparatus, the operation of which is controlled in accordance with data of a control command supplied from a data processing apparatus, on which data is written and from which data is read by the data processing apparatus, the external storage apparatus including: a serial signal I/O block for communicating data to the data processing apparatus by using serial signals; a control signal input block for receiving, from the data processing apparatus, a control signal for controlling timing at which data which is communicated to the serial signal I/O block is switched; and a synchronizing signal input block for receiving, from the data processing apparatus, a synchronizing signal of data which is communicated to the serial signal I/O block. The serial signal I/O block performs at least receiving data of a control command from the data processing apparatus, transmitting, to the data processing apparatus, a status signal indicating a state of the operation, receiving, from the data processing apparatus, data which is written thereon and transmitting, to the data processing apparatus, data which is read therefrom by using serial signals.
The serial signal I/O block switches the contents of data which is communicated in response to the control signal, and transmits, as a status signal, a ready signal having the signal level which is repeatedly changed at predetermined cycles when the state of the serial signal I/O block has been changed from a state in which the serial signal I/O block does not receive input of a signal from the data processing apparatus to a state in which the serial signal I/O block waits for input of a signal. The serial signal I/O block transmits a busy signal having a constant signal level as a status signal or pauses output of a signal when the external storage apparatus is performing a process in accordance with data of a control command and the external storage apparatus is in a state in which the external storage apparatus does not receive input of a signal from the data processing apparatus, and pauses output of a signal when an error has been made during receipt of data of a control command.
The external storage apparatus according to the present invention switches data which is connected by the serial signal I/O block in response to the control signal supplied from the data processing apparatus. When the external storage apparatus has been changed from a state in which the external storage apparatus does not receive input of a signal from the data processing apparatus to a state in which the external storage apparatus waits for the input of a signal, the external storage apparatus transmits a ready signal as the status signal, the ready signal having the signal level which is repeatedly changed at predetermined cycles. When the external storage apparatus performs a process in accordance with data of a control command and thus the external storage apparatus does not receive the input of a signal from the data processing apparatus, the external storage apparatus transmits, as the status signal, a busy signal having a constant signal level or pauses the output of a signal. When an error has been made in a period in which the external storage apparatus receives data of a control command, the external storage apparatus pauses the output of a signal.
According to the present invention, there is provided a data processing system for communicating data between a data processing apparatus and an external storage apparatus.
In the data processing system, the data processing apparatus incorporates a host side serial signal I/O block for communicating data to the external storage apparatus by using serial signals; a control signal output block for supplying, to the external storage apparatus, a control signal for controlling timing at which data which is communicated by the host side serial signal I/O block is switched; and a synchronizing signal output block for supplying, to the external storage apparatus, a synchronizing signal of data which is communicated by the host side serial signal I/O block. The host side serial signal I/O block performs at least transmitting data of a control command for controlling the operation of the external storage apparatus, receiving a status signal indicating a state of the operation of the external storage apparatus, transmitting data which is written on the external storage apparatus and receiving data which is read from the external storage apparatus by using serial signals.
On the other hand, the external storage apparatus incorporates an external serial signal I/O block for communicating data to the data processing apparatus by using serial signals; a control signal input block for receiving, from the data processing apparatus, a control signal for controlling timing at which data which is communicated by the external serial signal I/O block is switched; and a synchronizing signal input block for receiving, from the data processing apparatus, a synchronizing signal of data which is communicated by the external serial signal I/O block. The external serial signal I/O block performs at least receiving data of the control command, transmitting the status signal, receiving data which is written thereon and transmitting data which is read therefrom to and from the data processing apparatus by using serial signals.
The control signal output block of the data processing system makes the signal level of the control signal to be a predetermined level in accordance with data which is communicated between the host side serial signal I/O block and the external serial signal I/O block. When the state of the external serial signal I/O block has been changed from a state in which the external serial signal I/O block does not receive input of a signal from the data processing apparatus to a state in which the external serial signal I/O block waits for input of a signal, the external serial signal I/O block transmits, as a status signal, a ready signal having the signal level which is repeatedly changed at predetermined cycles. The external serial signal I/O block transmits a busy signal having a constant signal level as a status signal or pauses output of a signal when the external storage apparatus is performing a process in accordance with data of a control command and the external storage apparatus is in a state in which the external storage apparatus does not receive input of a signal from the data processing apparatus, and pauses output of a signal when an error has been made during receipt of data of a control command.
The data processing system has the structure that the signal level of the control signal which is supplied to the external storage apparatus is made to be a predetermined level in accordance with data which is communicated between the host side serial signal I/O block and the external serial signal I/O block. When the external storage apparatus has been changed from a state in which the external storage apparatus does not receive the input of a signal to a state in which the external storage apparatus waits for the input of a signal, the ready signal having the signal level which is repeatedly changed at predetermined cycles is transmitted from the external storage apparatus. When the external storage apparatus is performing a process in accordance with data of the control command and thus the external storage apparatus does not receive the input of a signal, the busy signal having a constant signal level is transmitted as the status signal from the external serial signal I/O block or the output of a signal from the external serial signal I/O block is paused. If an error is made when the external storage apparatus has received data of a control command, the output of a signal from the external serial signal I/O block is paused.
According to another aspect of the present invention, there is provided a data transmitting method for communicating data between a data processing apparatus and an external storage apparatus.
In the data transmitting method according to the present invention, the data processing apparatus incorporates a host side serial signal I/O block for communicating data to the external storage apparatus by using serial signals; a control signal output block for supplying, to the external storage apparatus, a control signal for controlling timing at which data which is communicated by the host side serial signal I/O block is switched, and a synchronizing signal output block for supplying, to the external storage apparatus, a synchronizing signal of data which is communicated by the host side serial signal I/O block. The host side serial signal I/O block performs at least transmitting data of a control command for controlling the operation of the external storage apparatus, receiving a status signal indicating a state of the operation of the external storage apparatus, transmitting data which is written on the external storage apparatus and receiving data which is read from the external storage apparatus by using serial signals.
On the other hand, the external storage apparatus incorporates an external serial signal I/O block for communicating data to the data processing apparatus by using serial signals; a control signal input block for receiving, from the data processing apparatus, a control signal for controlling timing at which data which is communicated by the external serial signal I/O block is switched; and a synchronizing signal input block for receiving, from the data processing apparatus, a synchronizing signal of data which is communicated by the external serial signal I/O block. The external serial signal I/O block performs at least receiving data of the control command, transmitting the status signal, receiving data which is written thereon and transmitting data which is read therefrom to and from the data processing apparatus by using serial signals.
The data transmitting method includes the steps of: making the signal level of the control signal which is transmitted from the control signal output block to be a predetermined level in accordance with data which is communicated between the host side serial signal I/O block and the external serial signal I/O block. When the state of the external serial signal I/O block has been changed from a state in which the external serial signal I/O block does not receive input of a signal from the data processing apparatus to a state in which the external serial signal I/O block waits for input of a signal, a ready signal having the signal level which is repeatedly changed at predetermined cycles is transmitted from the external storage apparatus. When the external storage apparatus is performing a process in accordance with data of a control command and the external storage apparatus is in a state in which the external storage apparatus does not receive input of a signal from the data processing apparatus, a busy signal having a predetermined signal level is, as a status signal, transmitted from the external serial signal I/O block or the output of a signal from the external serial signal I/O block is paused. If an error is made when the external serial signal I/O block receives data of a control command, output of a signal from the external serial signal I/O block is paused.
The data transmitting method has the structure that the signal level of the control signal which is supplied to the external storage apparatus in accordance with data which is communicated between the host side serial signal I/O block and the external serial signal I/O block is made to be predetermined level. When the external storage apparatus has been changed from a state in which it does not receive supply of a signal from the data processing apparatus to a state in which the external storage apparatus waits for the supply of a signal, a ready signal having a signal level which is changed at predetermined cycles is transmitted from the external storage apparatus. When the external storage apparatus is in a state in which it is performing a process in accordance with data of a control command and thus it does not receive supply of a signal from the data processing apparatus, a busy signal having a constant signal level is, as a status signal, transmitted from the external serial signal I/O block or transmission of a signal from the external serial signal I/O block is interrupted. If an error is made when data of a control command is received by the external serial signal I/O block, transmission of a signal from the external serial signal I/O block is interrupted.
Other objects, features and advantages of the invention will be evident from the following detailed description of the preferred embodiments described in conjunction with the attached drawings.